Overexpression of miR-34c regulates the sensitivity to doxorubicin in drug-resistant breast cancer cell lines MCF-7/DOX

摘要

Objective:To study the regulating effect of overexpressing miR-34c on the sensitivity to doxorubicin in drug-resistant breast cancer cell line MCF-7/DOX. Methods:Breast cancer cell lines MCF-7 and drug-resistant breast cancer cell lines MCF-7/DOX were cultured, transfected with miR-34c and negative control fragments and treated with different doses of doxorubicin;treated cells were taken, CCK-8 kits were used to detect cell viability, and RNA detection kits were used to detect mRNA contents of drug resistance-related genes. Results: miR-34a, 34b and 34c expression levels in MCF-7/DOX cell lines were lower than those in MCF-7 cell lines and the reduction of miR-34c expression level was the most significant, and mRNA contents of MDR1, BCRP, UCP2, Twist and c-Src were significantly higher than those in MCF-7 cell lines;after transfection of miR-34c, the inhibitory effect of doxorubicin on the viability of MCF-7/DOX cell lines was stronger than that of MCF-7/DOX cell lines transfected with negative control, and mRNA contents of MDR1, BCRP, UCP2, Twist and c-Src were significantly lower than those in MCF-7 cell lines transfected with negative control. Conclusions:Overexpression of miR-34c in drug-resistant breast cancer cell lines MCF-7/DOX can increase the sensitivity to doxorubicin and inhibit the expression levels of drug resistance-related genes MDR1, BCRP, UCP2, Twist and c-Src .